1. Field of the Invention
This invention relates to storage systems, and more specifically to remote copy of encrypted data from one storage system to another storage system.
2. Description of the Related Art
Encryption of data is commonly used to add some security to the data and to the transmission of the data. Further, copies of data are sometimes stored remotely at another storage system or storage device to serve as a backup should a primary storage system or storage device fail. However, problems arise should a storage system fail while in the process of encrypting the data. In this situation, it is not clear what data has been encrypted and which has not. Moreover, if multiple encryption techniques have been used, during a failure, it is not clear which data has been encrypted with which encryption technique and, therefore, which technique should be used to decrypt the data.
Information on DES (Data Encryption Standard) can be found on the Internet at www.itl.nist.gov/fipspubs/fip46-2.htm, and information on AES (Advanced Encryption Standard) exists at csrc.nist.gov/CryptoToolkit/aes/. Moreover, existing inventions in areas related to data encryption and data backup include: WO2002093314 A2 that discloses an encryption based security system for network storage, which provides an encryption based security system for network storage that separates the ability to access storage from the ability to access the stored data; U.S. Pat. No. 5,677,952 that discloses a method to protect information on a computer storage device, with which data in disks is encrypted and decrypted using keys derived from a password entered; U.S. Pat. No. 5,940,507 that discloses an information processing system providing archive/backup support with privacy assurances by encrypting data stored thereby; and U.S. Pat. No. 5,235,641 that discloses a file cryptographic method and file cryptographic system, which encrypts and decrypts data in storage systems. However, none of these provide solutions to the above-mentioned problems.
Therefore, there is a need for providing remote copy of encrypted data from one storage system to another storage system where if there is a failure at the first storage system during the encryption of data and remote copying of the data, the second storage system can decrypt the data using the appropriate method.